Physical characterization and dissolution properties of solid dispersions of the oxazepam with carbomer 934P

The formulation of solid dispersions is an effective method of increasing the dissolution rate of poorly soluble drugs. The purpose of this study was to prepare and to characterize solid dispersions of oxazepam with carbomer 934P to improve their dissolution properties. Solid dispersions were prepared by dissolution method and the dissolution rates of solid dispersions were compared with those ones of physical mixtures and pure drug. The evaluation of solid dispersions characteristics was performed using infrared espectroscopy (IR), X-ray diffractometry (X-R), differential scanning calorimetry (DSC) and dissolution assay. IR, X-R and DSC data showed no drug-polymer interaction. The results obtained from dissolution studies showed that the dissolution rate of oxazepam was considerably better when it was formulated in solid dispersions with carbomer 934P compared with those of physical mixtures and pure oxazepam.